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The Gordondale Member is a hydrocarbon source rock and potential unconventional reservoir that extends across northeastern British Columbia and central-northwestern Alberta. It is an organic-rich, calcareous, fossiliferous mudstone with a median total organic carbon value of 6.0 wt%. A total of 230 samples were collected from approximately 25 m of Gordondale Member core for organic matter analysis using Rock-Eval 6 analysis and organic petrology. Detailed core logging provides sedimentological context for organic matter characterization. The predominant organic material in the samples is solid bitumen and liptinite with lesser zooclast and inertinite. Most kerogen is Type II, autochthonous marine biomass, with minimal dilution by inert organic carbon. Rock-Eval Tmax values and random reflectance measurements of solid bitumen indicate the samples are within the oil generation window. Solid bitumen contributes a substantial amount of hydrocarbon potential to the interval. A micro-reservoir structure within the core is produced by thin intervals of impermeable displacive calcite that act as barriers to the upward migration of free hydrocarbons. These free hydrocarbon accumulations could make excellent targets for horizontal wells within the Gordondale Member.

The production of coalbed methane (CBM) represents a vital new source of natural gas supply in Western Canada. There are, however, concerns over potential negative environmental impacts on shallow groundwater resources in the hypothetical case that leakage of fluids and gases from CBM operations occurs. This paper compares major ion and isotope geochemistry data for produced fluids or gases from two major coal deposits in Western Canada (Mannville Formation and the Horseshoe Canyon/Belly River Group) with similar data collected for shallow groundwater in south-central Alberta. The objective was to generate comprehensive baseline geochemical data to determine the key geochemical characteristics and differences of produced fluids and gases from two coal deposits and shallow groundwater in Alberta and to find parameters that are suitable for identifying potential leakage of fluids or gases into shallow groundwater. Shallow groundwater had average total dissolved solids (TDS) of 1037 mg/L. Most samples belonged to the Na–HCO3–SO4 water type and average SO 4 2 - concentrations were 185 mg/L. The Horseshoe Canyon/Belly River Group swabbing fluids had average TDS of 5427 mg/L, a Na–HCO3 water type, and average SO 4 2 - concentrations of 47.7 mg/L. The produced fluids from the Mannville Formation had average TDS contents of 74,500 mg/L, negligible SO 4 2 - and a Na–Cl water type. Shallow groundwater and produced fluids from the Horseshoe Canyon Formation and the Mannville group had distinct δ2H and δ18O values and plotting δ18O values versus total dissolved solids was found to be an effective approach to distinguish the waters. Sulfur isotope data revealed the occurrence of bacterial (dissimilatory) SO4 reduction in some shallow groundwater samples and in the produced fluids from the Horseshoe Canyon/Belly River Group. Methane was found in several shallow groundwater samples and its average δ13C (−72.1 ± 6.8‰) and δ2H values (−297 ± 17‰) indicated a biogenic origin predominantly from CO2 reduction. Dissolved gases from the Horseshoe Canyon Formation fluids with average δ13C values of methane of −54.0 ± 4.1‰ and ethane of −36.5 ± 2.4‰ and traces of higher alkanes suggest a mixture of predominantly biogenic and some thermogenic gas. Dissolved hydrocarbon gas from the Mannville Formation had the highest average δ13C values of −49.4 ± 3.6‰ for methane, −28.8 ± 2.1‰ for ethane and −26.9 ± 1.1‰ for propane. The presence of higher alkanes suggests that the Mannville produced fluids contain an appreciable thermogenic gas component. The biogenic gas component in the Horseshoe Canyon and the Mannville Formation was mainly formed via acetate fermentation according to αCO2–CH4 values between 1.02 and 1.07. It is concluded that δ18O values of the fluids in concert with total dissolved solids, and the isotopic compositions of methane and ethane are sufficiently distinct in shallow groundwater and produced fluids from the Horseshoe Canyon and the Mannville Formations that they may serve as tracers for evaluating potential contamination of shallow groundwater with produced fluids or gases.

Bottom ashes collected from ESP and baghouse of seven pulverized coal-fired power plants using subbitumi- nous and bituminous coal and a fluidized bed combustor using crushed bituminous coal were examined for their mineral- ogy and elemental composition. The results presented in this paper are based on the average of three samples collected from each power plant. The mineralogy of each sample was determined using XRD and SEM/EDX; Elemental content was determined using INAA, ICPMS, and CVAAS; and the speciation of As, Cr, and Ni was determined by XANES. Bottom ash from the pulverized power plants consists of granular particles with a minor input of melted glassy fragments, while the bottom ash from the fluidized bed combustor consists entirely of granular particles. The sulphur and carbon con- tents of pulverized bottom ashes range from 0.03 to 2.32 wt % and 0.19 to 6.62 wt %, respectively. For the fluidized bed combustor, the sulphur and carbon contents were 5.27 wt % and 10.72 wt %. The concentrations of As, Cr, Hg, Ni, and Pb in bottom ash are related to sulphur content of coal and are higher for bottom ashes from high sulphur feed coals. Most of the elements associated with S (As, Hg, and Pb) are captured from fluidized bottom ash, more so than by the correspond- ing ESP fly ash. Most of the elements in bottom ash have enrichment (RE) factors of less than 0.7 indicating that they are not enriched in the bottom ashes as compared to the feed coals. Arsenic, Cd, Cr, Ni, and Pb have higher concentrations in granular bottom ash as compared to glassy bottom ash of the same power plant. The feldspars and quartz of feed coal are health hazards and are captured mostly by bottom ash and therefore prevent their emission from stack. The As, Cr, and Ni in form of: non-toxic As +3 , mostly beneficial Cr 3+ , and non-carcinogenic Ni 2+ are in coordination predominantly with oxygen. Mercury and Pb are low and have very little environmental impact.The hazardous elements (As, Cr, Ni, and Pb) are only leached by HCl, indicating that under normal condition they remain immobile and their impact on environment can be considered low.

Fine particles (PM 2.5 ) emitted from the stacks of the coal-fired power plants are of environmental concern since they can easily enter the human respiratory track. The detailed study of the fly ash particles using scanning electron microscope/electron dispersive spectrometry (SEM/EDX) show that fine solid spherical particles (microspheres) are contained by the large cenosphere particles (>50 μm) during the combustion process. The resulting macro particles are known as “plerosphere”, which are typically impregnated by the fine microspheres. The coal-fired power plants’ particle control devices such as the electrostatic precipitators (ESP) and baghouse filters tend to capture the large plerospheres, more efficiently. Therefore, the result of this study suggests that the containment of the microspheres by plerospheres during the coal combustion process can effectively reduce the amount of fine particles and associated elements released into atmosphere.

The Elk Valley coalfield of British Columbia is one of the major coal producing areas in Canada. The coals are of Cretaceous and Jurassic–Cretaceous age and range in rank from high-volatile to low-volatile bituminous (%Romax: 0.8–1.6). Coal seams from outcrops and active mines in this coalfield were analysed for rank and maceral composition using reflected light microscopy, for geochemistry using AAS, INAA, and ICPES, and also by proximate and ultimate analyses. The Elk Valley coal seams contain low average concentrations of hazardous elements such as As, Mo, Pb, and Se. However, there are seams that contain relatively high concentrations of some of these elements, such as 8 mg/kg and 108 mg/kg of arsenic. When the geochemistry of coal seams is compared within the different parts of the coalfield, the elemental composition amongst the seams from various sections located in the central area of the coalfield is similar. Coal seams in the northern area of the coalfield have different geochemistry than coal seams in other areas of the coalfield; seams in the northern area have much higher As, Br, Cr, Cu, Fe, K, and Na content, but contain less Ca.

Fly ashes produced from Canadian power plants using pulverized coal and fluidized bed combustors were examined for their carbon content to determine their ability to capture mercury. The feed coal used in these power plants were lignite, subbituminous, high and medium volatile bituminous, their blends, and also blends of coal with petroleum coke (Petcoke). The carbon and mercury content of the coals and fly ashes were determined using the ASTM standard method and by the cold vapour atomic absorption spectrometry method. The carbon content of the fly ash was concentrated by strong acid digestion using HCl and HF. The quantitative and qualitative analyses of the carbon concentrate were made by using a reflected light microscope. The results show that the carbon content of fly ash appears to be partially related to depositional environment during coalification and to the rank of the coal. The Hg captured by the fly ash depends on the rank and blend of the feed coals and the type of carbon in the fly ash. The isotropic vitrinitic char is mostly responsible for the capture of most Hg in fly ash. The inadvertent increase in carbon content due to the blending of coal with petroleum coke did not increase the amount Hg captured by the fly ash. The fly ash collected by the hot side electrostatic precipitator has a low Hg content and no relation between the Hg and carbon content of the ash was observed. These results indicate that the quantity of carbon in the fly ash alone does not determine the amount Hg captured. The types of carbon present (isotropic and anisotropic vitrinitic, isotropic inertinitic and anisotropic Petcoke), the halogen content, the types of fly ash control devices, and the temperatures of the fly ash control devices all play major roles in the capture of Hg.

Feed coals and fly ashes from two coal-fired power plants burning Alberta subbituminous coal were analyzed for C, Cl, Hg, and S and calorific values (for feed coal only), every week for a period of 33 weeks. The feed coals used in this study were deposited in brackish water and are compared to the coals deposited in a freshwater environment. The Hg and char (unburnt carbon) content of the fly ash was monitored to determine the variation of Hg and its possible relationship to the char types in the fly ash. The feed coals have Hg content of 0.026–0.089 mg/kg and their fly ash contains 0.02–0.243 mg/kg of Hg. The C content of the fly ashes ranges from 0.15% to 0.51%. The carbon/char was separated from the fly ash using HF and HCl. Reactive vitrinitic (formed from woody part of plants) and less reactive inertinitic (natural char) chars were separated by density separations of various specific gravities using ZnBr 2 . The char is mostly reactive vitrinitic (67–80 vol.%). Both stations have similar range of C content for their respective fly ashes. However, station 2 shows a much wider range of Hg in fly ash compared to station 1. In general, the fly ash from coal deposited under brackish water environment (stations 1 and 2) appears to have same or higher Hg content for lower C content compared to the fly ash from coal deposited under fresh water environment. The calculated emitted Hg for the period of 33 weeks for station 1 is estimated to be 64–90% of the total input of Hg with an average of 74%. The calculated emitted Hg shows a more complex pattern for station 2 and falls into two groups; with group (a) showing higher enrichment index for both Hg and S. The calculated emitted Hg for this group is 43–74% with an average of 57%, indicative of more Hg being captured by fly ash, possibly due to interaction between Hg and S. In the second group (b) the emitted Hg is calculated to be 74–95% with an average of 85%. The relative enrichment of both Hg and S in group (b) is low compared to group (a), indicative of possible slight paleo-weathering of the feed coal. The present study indicates that geological parameters such as paleo weathering and also depositional environment of the feed coal may influence the Hg content of fly ash.

This study addresses the physical geochemical aspects of the relationship between Hg and organic matter in recent sediment from eutrophic lakes in central Alberta, Canada. The types of organic matter in the sediment are classified based on their degree of thermal degradation and their petrographical characteristics. This study uniquely applies the methods conventionally used in petroleum geosciences (Rock-Eval® analyses and organic petrology) to investigate the relationship between various types of organic matter and the concentration of Hg in sediment. The results show that the total organic carbon (TOC) in sediment represents the sum of various organic compounds, which may play a completely different role in the distribution and accumulation of Hg. Strong correlations between TOC and the concentration of Hg in the studied sediment arise mainly from the thermally labile portion of organic matter released during pyrolysis under 300 °C. These compounds primarily consist of easily degradable algal-derived lipids and various pigments, which are petrographically described as soluble organic matter (SOM). The preserved SOM in sediment is commonly entrapped within the cell walls of phytoplankton and also appear as surface coating on sediment particles. The strong affinity between Hg and SOM is due not only to its chemical reactivity, but also to the physical characteristic of these labile compounds. The SOM may provide a substrate with enormous surface area by concentrating on the finer sediment size fractions and potentially acting as a “concentrator” for Hg and other organic-associated elements. Lastly, the quantity of the SOM has been calculated as an “elemental concentrator” portion of the TOC, which plays the most important role in the distribution of Hg in sediment.

The distribution of aerially deposited metals, As, Cd, Cu, Hg, Pb and Zn, was studied using passive collection moss monitoring in the vicinity of the smelter in Trail, British Columbia, Canada. The concentrations of metals/metalloids were measured in moss bags exposed to atmospheric deposition for periods of three months. The results show the greatest deposition of metals proximal to the smelter, and a decrease in deposition with increasing distance from the smelter. The pattern of deposition varies with the season, the element under study, and the location of the monitoring station. The depositional pattern around the Trail smelter is controlled mainly by the physiography of the region as related to shape and orientation of the Columbia river valley and direction of the prevailing wind. The results show that the annual aerial deposition of metals is directly related to the quantity of stack-emitted metals and Pb–Zn production levels. The distribution of Pb, Zn and Cd in surface soils around the Trail smelter shows a similar pattern to their deposition at moss-monitoring stations. These soils are characterized by an elevated concentration of metals in the proximity of the smelter, indicating the effect of airborne materials on the geochemistry of the soils in the study area. Such similarity was not found for Hg, Cu and As, indicating that the variation of these elements in soil samples is more likely related to soil chemistry rather than to atmospheric deposition.

Fly ashes were collected from the electrostatic precipitator (ESPs) and/or the baghouse of seven coal-fired power plants. The fly ashes were sampled from power plants that use pulverized subbituminous and bituminous feed coals. Fly ash from bituminous coals and limestone feed coals from fluidized-bed power plant were also sampled. The fly ashes were examined for their mineralogies and elemental compositions. The fly ashes from pulverized low sulfur coals are ferrocalsialic, those from high sulfur coals are ferrosialic and the fly ashes from the fluidized bed coals are ferrocalcic. The concentrations of As, Cd, Hg, Mo, Ni, and Pb in fly ash are related to the S content of the coal. Generally, those feed coals with a high S content contain higher concentrations of these elements. The concentrations of these elements are also greater for baghouse fly ash compared to ESP fly ash for the same station. The S content of fly ash from high S coal is 0.1% for pulverized ESP fly ash and 7% for baghouse fly ash from the fluidized bed, indicating that most of the S is captured by fly ash in the fluidized bed. The baghouse fly ash from the fluidized bed has the highest content of Cd, Hg, Mo, Pb, and Se, indicating that CaO, for the most part, captures them. Arsenic is captured by calcium-bearing minerals and hematite, and forms a stable complex of calcium or a transition metal of iron hydroxy arsenate hydrate [(M 2+ ) 2 Fe 3 (AsO 4 ) 3 (OH) 4 ·10H 2 O] in the fly ash. Most elements in fly ash have enrichment indices of greater than 0.7 indicating that they are more enriched in the fly ash than in the feed coal, except for Hg in all ESP ashes. Mercury is an exception; it is more enriched in baghouse fly ash compared to ESP. Fly ash collected from a station equipped with hot side ESP has a lower concentration of Hg compared to stations equipped with cold side ESP using feed coals of similar rank and mercury content. Fly ash particles from fluidized bed coal are angular and subangular with cores of quartz and calcite. The quartz core is encased in layer(s) of calcium-rich aluminosilicates, and/or calcium/iron oxides. The calcite core is usually encased in an anhydrite shell.

Upper Triassic to Middle Jurassic coals from the Alborz region of northern Iran were analyzed by reflected light-fluorescence microscopy and Rock Eval 6® pyrolysis to evaluate their regional rank variation, degree of hydrothermal alteration, and petroleum generative potential. The coal ranks in the region range from a low of 0.69%RoR in the Glanddeh-Rud area to a high of 1.02%RoR in the Gajereh area. Tmax (°C) values (Rock Eval 6 pyrolysis) also increase progressively with increasing vitrinite %Ro values, however Tmax is suppressed lower than would be expected for each rank ranging from 428 °C for the Glandeeh coal to 438 °C for the Gajereh coal. Tmax suppression may be caused by maceral composition and soluble organics within the coal. Moderately high hydrogen indices, persistent and oily exudations from the coals during UV exposure, and traces of hydrocarbon fluid inclusions suggest that liquid petroleum was likely generated within some of the coals.

Particles emitted from coal-fired power plants burning subbituminous coal from Alberta, Canada were examined for total particulates (PM) and size fractions PM>10, PM10, and PM2.5. The sampling was carried out following EPA Method 201A. Three tests were performed at each station. The emitted particles were examined using SEM/EDX and gravimetric method for the determination of their sizes. The elemental composition of particles was determined using INAA and ICP-MS. The particles emitted from the stack are classified based on their morphologies and chemistries to the following: unburnt carbon, feed-coal minerals such as quartz, and by-products of the dissociation, fractionation, and contamination by minerals in coal. The emitted particles are mostly spherical and their matrices are composed of aluminosilicate minerals containing calcium. The PM>10 fraction contains small plerospheres, fragments of char, and angular quartz and feldspar particles. The PM10 fraction contains solid spheres and cenospheres, gypsum needles, and particles of char. The PM2.5 particle size fraction is mostly composed of solid spherical aluminosilicates with some surface enrichment of elements such as Ba, Ca, and Fe. The composition of emitted particles is ferrocalsialic. Most elements in the particle size fractions are Class I or II, such as Al, Ca, and Fe. Cd, Cu, Mo, and Ti were only detected in PM2.5 fraction.

Feed coals and fly ashes from a coal-fired power station burning Alberta subbituminous coal were examined for a period of thirty-eight weeks to determine the variation in emitted mercury. Feed coal samples were analyzed for proximate, calorific value and Hg content, while fly ash samples were examined for C and Hg contents. The maceral content of the feed coal was also determined. The emitted mercury was calculated and compared to mercury emitted from the stack according to a mass-balance calculation from a previous study for the same station. Mercury contents ranged from 0.029 to 0.066 mg/kg for feed coal, and from 0.069 to 0.112 mg/kg for fly ash. The carbon/char in fly ash was separated into reactive (vitrinitic/bimacerate) and less reactive (inertinitic) chars using ZnBr2 at specific gravities of 1.7, 2.0, and 2.25 to 2.4. The result shows that there is a positive correlation between the carbon and mercury content of the fly ash. The reactive char particles in the fly ash may be responsible for the capture mercury in fly ash. The percentage of estimated captured mercury by fly ash increases with increasing carbon content (%) in fly ash. The percentage of emitted mercury for the period of 38 weeks is estimated to be within the range of 49% to 76% of the total input of mercury.

This study is related to four Jurassic-age bituminous coal (0.69–1.02 Ro%) samples collected from coal mines from the west, central and east of central, Alborz in northern Iran. Geological settings played key roles in determining the geochemistry and mineralogy of coals from the central Alborz region of northern Iran. The mineralogy of coals from the eastern part of the region is dominated by kaolinite; halloysite; and carbonates such as calcite, dolomite/ankerite, and siderite. The coals were deposited in a lacustrine environment. In the western part of the region, where the depositional setting was also lacustrine with volcanic input and tonstein deposition (glass shards present), the coal primarily contains kaolinite (68%) and fluorapatite (26%). In contrast, coal from the central part of the region, which was deposited in a terrestrial environment and on eroded limestone and dolomite rocks, is dominated by dolomite (98%) with little input by kaolinite. These coals have low sulphur (0.35–0.70 wt.%), which is mostly in the organic form (0.34–0.69 wt.%). Pyritic sulphur is detected only in one coal and in small quantities. The boron contents of these coals range from 9 to 33 mg/kg, indicating that deposition occurred in a fresh water environment. Coal with higher concentrations of Ba, Sr, and P contain fluorapatite and goyazite–gorceixite series [BaAl 3 (PO 4 ) 2 (OH) 5 , H 2 O] minerals, which indicates volcanoclastic input. Compared to world coal averages, these coals exhibit low concentrations of elements of environmental concern, such as As (1.3–5.9 mg/kg), Cd (

Fifty-six samples of stream sediments from 12 creeks in the vicinity of Trail, British Columbia, Canada were examined to determine their origin, characterize their organic matter and their relation to natural/geogenic and anthropogenic sources. The samples were initially screened by Rock-Eval® 6 pyrolysis for their TOC, HI, and OI contents and then examined by both reflected (polarized) and fluorescent light microscopy. It was found that organic matter in stream sediments is mostly from natural/biological sources from local vegetation, such as woody tissue, suberin, spores, and pollen, as well as altered natural/biological input from char formed due to forest fires. Anthropogenic organic matter, mostly coke particles, was also found in the stream sediments. The coke particles have anisotropic properties with medium grained texture formed from medium volatile bituminous coal. The occurrence of coke particles is limited to Ryan Creek located close to an area were some small gold, nickel, and lead smelting operations previously occurred. There is no evidence to indicate that the coke particles found in the creek are emitted from the lead and zinc smelter currently in operation in the area. There are no coal-bearing strata in the area that may have a direct input of coal fragments in any of the creeks.

The chromium species in the feed coals and ash byproducts from seven Canadian coal-fired power plants were examined using Cr X-ray absorption near-edge spectroscopy. Chromium in the Canadian feed coals is always found as Cr{sup 3+} but generally has a dual occurrence, as Cr{sup 3+} is distributed to varying degrees between the clay mineral illite and a poorly crystallized chromium oxyhydroxide phase associated with the organic fraction. In two subbituminous feed coals from Alberta, chromium is present largely as Cr{sup 3+}/illite, whereas in two other such coals, it is present predominantly as CrOOH. Chromium in a low-sulfur bituminous feed coal from Alberta is found mostly as Cr{sup 3+}/illite, whereas for feed coals from Nova Scotia with high sulfur contents, chromium is distributed between both Cr{sup 3+}/illite and CrOOH. Very little chromium was found in the limestone used in a fluidized-bed combustor. The chromium species in most bottom ash samples from all seven combustion units is predominantly, if not entirely, Cr{sup 3+} associated with aluminosilicate phases. Chromium speciation for subbituminous electrostatic precipitator fly ash is mostly Cr{sup 3+}, but in some cases, it is slightly lessand varies by sampling location at the plant. Chromium in fly ash from the combustion ofmore » bituminous feed coals is predominantlyCr{sup 3+}. A unique species of chromium found in one feed coal and an unrelated fly ash is metallic chromium, similar to that in stainless steel. The occurrence of this form of chromium in these materials indicates contamination from machinery, such as the coal milling machine or possibly wearing down of stainless steel parts by the coal or ash. The observation of this unexpected contamination demonstrates the power and usefulness of X-ray absorption fine-structure spectroscopy for speciation determination. 35 refs., 6 figs., 4 tabs.« less

This study characterizes the petrological changes occurring in an organic matter assemblage of Recent lacustrine sediments from Alberta, Canada, during the various steps of Rock-Eval 6® pyrolysis. The results indicate that the organic compounds released during pyrolysis at low temperatures of up to 300 °C (mainly S1-compounds) are most likely derived from a ‘stain-like’ amorphous organic matter, including pigments and oils/lipid products with strong, multicolored VIS fluorescence. The fluid characteristics of the thermally labile S1-compounds possibly account for the significant grain surface coating by the organic matter. Thermal alteration of sediments at 300 °C results in the transformation of some alginite and other macerals into a secondary product of blue–green fluorescing bitumen, which migrates into available free spaces. The release of S2-compounds during high temperature pyrolysis (from 300 to 650 °C) causes severe alterations in the morphology of the liptinitic organic matter. A bright yellow fluorescence that appeared at this stage is likely due to thermal transformation of bitumen produced in S1 pyrolysis and other liptinitic macerals into an “oily-material”, which fills cell lumens and becomes incorporated into the mineral matter. Neither the rapid rate of heating nor the sample residence time during Rock-Eval pyrolysis are sufficient for complete thermal destruction of the secondary hydrocarbon and bitumen products produced in the sample.

The arsenic species in the feed coals and ash byproducts from seven Canadian power plants (including one with a fluidized-bed combustor) that were burning local sub-bituminous and bituminous coals with sulfur contents in the range of 0.30−3.5 wt % have been examined using As X-ray absorption fine structure (XAFS) spectroscopy. The feed coals can be grouped based on their contents of arsenic associated with pyrite (As/pyr) and as As3+ and As5+ (arsenate) species. The arsenic species in sub-bituminous feed coals with low sulfur (0.22−0.38 wt %) and arsenic (1.6−2.2 mg/kg) contents consist of ∼50% As3+ and ∼50% As5+, whereas those with moderate sulfur (0.50 wt %) and arsenic (3.63 mg/kg) contents consist of 84% As/pyr, 7% As3+, and 9% As5+. In bituminous feed coal with low sulfur (0.40 wt %) and arsenic (4.39 mg/kg) contents, the arsenic speciation consists of 34% As/pyr, 12% As3+, and 54% As5+, and for those with high sulfur (2.60−3.56 wt %) and arsenic (54−84 mg/kg) contents, it consists of 77%−82% As/pyr ...

The mercury and maceral content of subbituminous feed coals burned at six Canadian power plants was measured and compared to the mercury and carbon content of corresponding fly ashes. The fly ashes were collected from electrostatic precipitator (ESP) pollution controls used at the power plants. Four feed coals from the Upper Cretaceous to Tertiary age Scollard Formation were deposited in freshwater depositional environment and contain 35–44% inertinite. Two feed coals from the Upper Cretaceous age Horseshoe Canyon Formation were deposited in a brackish water environment and contain 14% inertinite. The data show that abundant inertinite equates to more unburned carbon in ESP fly ash, and to enhanced capture of mercury in cold-side ESP fly ash. This indicates that the inertinite content of a coal seam may be indicative of the percentage of unburned carbon and the percentage of mercury captured by a cold-side ESP.

Western Canadian subbituminous coal is mined using strip-mining methods. The coal is used to feed coal-fired power plants for electricity generation. Parameters that influence the mercury content of these coals include the occurrence and frequency of partings in the seam, weathering, and epigenetic mineralization. Most partings have higher mercury content than the coal layers in the same seam, with the single bentonite bed having the highest Hg content. However, some high ash components, such as sandy siltstone, do not follow this trend. The incorporation of the high mercury partings into the as-mined coal may increase the Hg content in the feed coal. Epigenetic mineralization may also increase the mercury content of coal, depending on the nature of the mineralization. Calculation of the weighted mean of mercury content for various combination of lithological components of a seam illustrates how these components influence the total mercury content of the seam. This approach also suggests how selective mining might be used to reduce mercury in “as-mined” coal. Results of weighted average calculations of mercury indicate that the thin lithological units with moderate mercury may not necessarily influence that overall weighted average of Hg for a seam. However, there can be exception, such as presence of thin (3.5 cm) bentonite parting with high mercury in a 94.5 cm seam that increased the mercury content of seam by 83.4%.

The quantities of six elements (As, Cd, Cu, Hg, Pb, and Zn) were determined in surface soil from 21 stations around the zinc–lead smelter in Trail, British Columbia, Canada. The flux of elements into a unit of soil was then calculated by extrapolating aerial deposition monitoring data obtained from flat square moss bags, which act as traps for airborne particles/elements. The net increase in the quantity of elements in a 10 cm deep by 1 hectare soil unit over a 3-month time interval was estimated as 0.02, 0.65, 0.07, 0.29, 0.22, and 0.65% for As, Cd, Cu, Hg, Pb, and Zn, respectively. The results of this study can be used for elemental inventory of soil in the Trail area and to predict the long-term degree of accumulation of trace elements in the soil. The significant correlation between the deposition rate of Pb, Zn, Cd, and Cu as registered by moss monitoring stations and the quantity of these elements in surface soil indicate the possible effect of airborne material on the geochemistry of the soils in the study area. In contrast, the poor correlation for Hg and As indicates that the variations of these elements in soil samples are likely related to soil chemistry rather than atmospheric deposition. This demonstrates the importance of monitoring for atmospheric deposition of elements since soil is not always a good indicator of the spatial influence of a point source in the study area.

Feed-coals used in some Canadian power plants were examined for their mineralogical and elemental composition. The mode of occurrence of elements (organic/minerals) in these samples were determined using sequential leaching by H 2 O, NH 4 OAc and HCl. Canadian feed-coals examined in this study are subbituminous to bituminous rank (calorific values: 19.62–29.88 MJ/kg). The sulphur content of these coals is 0.32–3.55%. Quartz and aluminosilicates (clay minerals and feldspar) dominate the mineralogy of these samples. The accessory minerals consists of pyrite, sphalerite, barite, calcite, anhydrite, chromite, zircon, biotite, and monazite, which occur as both primary and secondary cell filling types. An interesting mineral found in one of the subbituminous feed-coals is the gorceixite that is normally associated with degraded volcanic ash. The sulphur content of the feed-coals is an indication of their geological setting with feed-coal formed in a fresh water setting containing the least amount of S and those associated with evaporites having the highest S content. The concentrations of Cd, Cr, Cu, Hg, Ni, Se, V, and Zn in these Canadian feed-coals are low compared to world coals. Mercury content of these feed-coals ranges from 0.04 to 0.16 ppm. Mercury is mostly associated with the pyretic portion of coal and has direct correlation to As and S content in these coals. Arsenic in low sulphur coals is mostly associated with coal macerals and in higher sulphur coals with pyrite. About 47% of As in high sulphur coal is removed after leaching by HCl. Water soluble elements consist of Co, Ni and Mn, which are associated only with bituminous feed-coals. The removal of these elements by water is possibly due to an increased acidity of leaching solution and presence of soluble Cl and S. Beryllium and vanadium in low S coals are mostly removed after leaching by HCl, indicating a possible association with clay minerals. Limited Be and V is removed from lower clay mineral content coals; however, in high S content coals, more Be and V are removed. The speciation of As, Cr and Ni indicates that As is mostly present in the less-toxic form As +5 and Cr is present entirely as Cr 3+ , an essential human trace nutrient, found in both subbituminous and bituminous ranked coals. Nickel is present mostly as Ni 2+ in oxygen coordination in these milled coals and carcinogenic compounds of nickel are not present in these feed-coals.

The atmospheric deposition and regional dispersion pattern of the elements As, Cd, Cu, Hg, Pb and Zn, emitted from Pb-Zn smelters at Trail, British Columbia, Canada, were studied for a period of two years using the passive collection moss-monitoring method. Concentrations of these elements in moss bags, exposed to atmospheric deposition for three months, were first corrected for geogenic input and then site-specific local background level to produce common background elemental concentrations for all monitoring stations. The results of this study indicate that the deposition of these elements is greatest in proximity to the smelter and decreases with an increase in distance. The regional dispersion pattern generally varies seasonally, with the magnitude of variation being dependent on the element under study and the location of the monitoring station. Overall, the deposition of these elements (as registered by moss-monitoring stations) appears to be a complex phenomenon involving various factors such as meteorological conditions (prevailing wind direction and precipitation), physiography (topography, valley shape and orientation) and in-process activities at the smelters (production level, emission control efficiency and the geochemistry of feed). However, the results of this study indicate that, on an annual basis, in-process activities, particularly production levels of Pb and Zn and the quantity of emissions from the stack, are more directly related to the observed deposition of the elements than any of the other factors.

Mineralogy and elemental contents were determined on 18 samples from a vertical profile of the No. 2 seam, Genesee mine, AB. The samples analyzed consist of coal, coaly shale, shaly coal, carbonaceous shale, shale, mudstone and siltstone. Proximate analysis was determined on all samples. Elemental analyses were determined by instrumental neutron activation analysis (INAA) for all elements except As, B, Cd, Hg, Mo, Pb, Se (Atomic Absorption) and B, Ba, Be, Co, Cr, Cu, Li, Mn, Nb, Sr and V (inductively coupled plasma-emission spectroscopy, ICP-ES). Samples were low temperature ashed (LTA), X-ray diffraction (XRD) and X-ray fluorescence (XRF) were used to determine quantitative major mineralogy. Accessory mineralogy was determined with Scannining Electron microscope/energy dispersive X-ray analyzer (SEM/EDX) on four samples. In general, the coals in the Genesee mine are within the low end of the range for trace element contents given by Swaine [Swaine, D.J., 1990. Trace Elements in Coal. Butterworths, London, 278 pp.] for most coals. High contents of Cr (9–2620 ppm) and Ni (1–1440 ppm) can be related to an increased amount of a Cr–Ni–Fe oxide (chromite–magnetite?) likely derived from ultrabasic diatremes in the Golden-Columbia Icefields, BC area. The No. 2 seam of the Genesee mine can be divided into two geochemical cycles on the basis of mineralogy, trace element contents and rare earth element (REE) behavior. Cycle I consists of quartz, calcite and kaolinite, lower trace element contents, REE slightly enriched in high rare earth elements (HREE), and thick coal with few partings. Cycle II consists of quartz, calcite, kaolinite, illite, mixed layer and/or expandable lattice clays, feldspar, gypsum, calcium aluminum sulfate hydrate, clinoptilolite, calcite and diopside, higher trace element contents, REE slightly enriched in light rare earth elements (LREE) and thin coal with a greater frequency of partings. The differences between the two geochemical cycles can be accounted for by a decreasing stability of the peat-forming environment resulting from an increasing fluvial influence and volcanogenic input.

This article examines the chemical fractionation (leaching) of elements from the Whitewood Mine subbituminous coals and coal ashes at 120 C, 750 C, and 1000 C. The elements Ba, Zn, and Mn are easily leached from coal by water, ammonium acetate, and hydrochloric acid. Potassium is highly extractable by NH4O acetate but very little with HCl. Hydrochloric acid leaches most of Fe, whereas very small quantities of the element are leached by water or NH4O acetate. Low extractability from coal was noted for Si, Ti, and Cu, an indication of their association with detrital minerals. Extractability of Na from coal was low, which indicates an association with minerals rather than being in the form of exchangeable ions. High leachability for Ca, Sr, and to a certain degree, Mn, Mg, and Na were noted for the 120 C ash samples. Zinc, Ba, S, and P showed a wide variation, reflecting a complex association with carbonate, sulphate, sulphide minerals, and organic matter. Silica, Al, B, Li, Cu, and Mo were completely insolu...

Determining thermal maturity studies in the Ellef Ringnes Island area was complicated by numerous factors, such as the presence of cavings, bitumen staining, and igneous intrusions. Cavings are a problem in certain intervals in Hoodoo H-37, Dome Bay P-36, and Helicopter J-12. Bitumen staining resulting in suppression of reflectance has occurred in the lower part of the Jameson Bay shales in Elve M-40. Thick sills resulted in increase of Ro to 4.0%, whereas thin sills had a minimal impact on reflectance increase. Other features observed include overpressuring caused by hydrocarbon generation in the Schei Point source rocks as well as in the Jameson and Ringnes shales, and a “kinky” Ro profile caused by the presence of low-permeability gas-bearing reservoirs in the Heiberg sandstones in Jackson Bay G-16A. The presence of sapropelic coals with HI up to 329 mg HC/gTOC in Heiberg sandstones in Elve M-40 containing Botryococcus algae should also be noted. Calculated maturation gradients vary from 0.95 ...

Selected high to medium volatile bituminous coal seams of Carboniferous age from the Sydney and Stellarton Basins, Nova Scotia, Eastern Canada were analyzed for their organic and inorganic components. These studies evaluated: (a) the evolution of the ancestral mires (coal facies) that formed various seams; (b) the lateral and vertical distribution of various elements within coal facies (lithotypes); and (c) the mode of occurrence of various elements. Coal facies fluctuated between rheotrophic and minerotrophic mires with occasional flooding or drowning of the mire forming inorganic partings. These partings are the source for most lithophile elements including B, Cr, U, V, and rare earth elements. Most of the lithophile elements are associated with a distinct, mainly syngenetic, mineral phase (associated with the clay minerals), which is derived from the erosion of a hinterland source. Chlorine, Ca and minor amounts of As and Mn are organically bound. Arsenic is mostly associated with fine-grained framboidal pyrite as solid solution. Other chalcophile elements such as Cu, Pb, and Zn in the Sydney Basin occur as a syngenetic sulfide mineral phase, whereas these elements in the Stellarton Basin are associated with syngenetic and epigenetic sulfides. Arsenic, Cl, and Mo and part of the Cu and Pb are possibly derived from a mineralized brine that was originated from the dissolution of Windsor Group evaporites. The lateral variation of elements suggests that the coal beds in the Sydney Basin are enriched in As, Cl, Mn, and Pb whereas those of the Stellarton Basin are enriched in Cr and Ni. The Donkin resource block of the Sydney Basin has the lowest concentration of As, Mn, Ni, and Pb, which make it attractive from a development perspective.

Organic-rich from the Schei Point group (middle to late Triassic in age) and the Ringnes formation (late Jurassic) from the Sverdrup basin of the Canadian arctic archipelago have been geochemically evaluated for source rock characterization. Most samples from the Schei Point group are organic-rich (> 2% TOC and are considered as immature to mature oil-prone source rocks [kerogen types I, I–II (IIA) and II (IIA)]. These kerogen types contain abundant AOM1, AOM2 and alginite ( Tasmanales, Nostocopsis, Leiosphaeridia , acritarch and dinoflagellate) with variable amounts of vitrinite, inertinite and exinite. Samples from the Ringnes formation contain dominant vitrinite and inertinite with partially oxidized AOM2, alginite and exinite forming mostly immature to mature condensate- and gas-prone source rocks [kerogen type II–III (IIB), III and a few II (IIA)]. Schei Point samples contain higher bitumen extract, saturate hydrocarbons and saturate/ aromatic ratio than the Ringnes samples. Triterpane and sterane (dominant C 30 ) distribution patterns and stable carbon isotope of bitumen and kerogen suggest that the analyzed samples from the Schei Point group are at the onset of oil generation and contain a mixture of sapropelic (algal) and minor terrestrial humic organic matter. Sterane carbon number distributions in the Ringnes formation also suggest a mixed algal and terrestrial organic matter type. There are some variations in hopane carbon number distributions, but these are apparently a function of thermal maturity rather than significant genetic differences among samples. Pyrolysis-gas chromatography/mass spectrometry of the two samples with similar maturity shows that the Schei Point sample generates three times more pyrolyzate than the Ringnes sample. Both samples have a dominant aliphatic character, although the Ringnes sample contains phenol and an aromaticity that is higher than that of the Schei Point sample.

This study reports on the elemental concentrations and vertical variation of coal seams from the Obed Mountain deposit, Alberta Foothills, Canada. Results from two sections of Seam 1 show that the major elements (i.e. Al, Fe, Mg, K, Na, Ti, and Si) have high concentrations in intervals having high ash content, with the only exception of Ca. Similarities are apparent, in both sections, in the vertical variations of Th, U, Se, and Zn; Rb, Cs, and K; Sb, Mo, and W; Mn and Sr; and Ba, Cr, Co, Hf, and Sc. These similarities are also evident among the REEs, notably between Ce and La; also between Dy, Eu, and Sm. Most elements, with the exception of Ba and Sr are slightly more concentrated in Section 2 of Seam 1, located approximately 1.5Fig. km away from Section 1. Compared to Seam 1, Seam 2 has lower mean concentrations of elements. Boron in the coal ranges from 27 to 100 ppmw, though most values are less than 50 ppmw. Boron concentrations suggest a freshwater depositional environment. The element is depleted in the sedimentary partings (12–29 ppmw only) and is enriched in the coal interval near the roof and immediately beneath the partings. This enrichment shows possible downward mobilization of boron. Vertical variations of elements are helpful in delineating the boundaries between coal and sedimentary partings in the succession. The Obed Mountain coals are “clean” by world standards and their elemental concentrations are comparable with those in coals of a lower rank from the same coal formation used for power generation in Alberta. All sedimentary partings have low concentrations of Ba, Hf, Sc, Sr, Ta, Th, U, and REEs; this, along with the absence of an Eu negative anomaly suggests a non-volcanic origin for the partings.

Concentrations of the elements As, B, Br, Cl, Cr, Mn, Na, Sb, Th, U, V, and Zn were determined in ply-by-ply samples from two sections of subbituminous coal from seam 3, Vesta Mine, Alberta Plains. The elemental mean concentrations in section 1 were As l.0 ppm, B 215ppm, Br 2.3ppm, Cl 29ppm, Cr 7.4ppm, Co 1.1 ppm, Mn 24.5 ppm, Mo 2.5 ppm, Na 4900ppm, Sb 0.4 ppm, Se 0.8 ppm, Ti 270 ppm, U 1.4 ppm, Th 2.8 ppm, V 2.9 ppm, and Zn 9.5 ppm. In section 2, the mean concentrations were As 0.7 ppm, B 201 ppm, Br 1.6 ppm, CI 24 ppm, Cr20ppm, Co 1.7 ppm, Mn 30.0ppm, Mo 2.8ppm, Na 4200ppm, Sb 0.3 ppm, Se 0.7ppm, Ti 340ppm, U 0.8 ppm, Th 1.8 ppm, V 4.4 ppm, and Zn 68 ppm. Total sulfur content averaged 0.44% in section 1 and 0.48% in section 2. Mean concentrations of these elements are low when compared to western Canadian coals of similar rank, or to world coals (Swaine, 1990). Antimony, barium, and boron are enriched, with the latter being a reflection of the coal-forming environment. Despite the short lateral distanc...

The hydrocarbon source rock potential of the Devonian Marcellus and Kettle Point black shales in southern Ontario has been assessed using Rock-Eval pyrolysis, gas chromatography, gas chromatography-mass spectrometry and incident-light microscopy. Both formations contain sufficient hydrogen-rich organic matter (Type II) to be considered possible source rocks. The kerogen is predominantly marine in origin. This organic matter was deposited in a clastic algal-dominated environment, and mainly consists of unstructured bituminite and unicellular alginite. The organic microfacies indicate shelf paleodepositional settings with a transition to an open basinal region. The optical (reflectance, fluorescence) and geochemical (Rock-Eval Tmax, extract yields, distributions of steranes and terpanes) maturity data indicate that the organic matter in the Kettle Point Formation is immature, whereas in the Marcellus Formation it has reached the early stages of hydrocarbon generation and expulsion. Some Devonian oils occurring in this area have characteristics similar to the Marcellus extracts, suggesting that more mature equivalent units from the Appalchian Basin could be their source.

The coal-bearing strata in the Basoren Formation from the Sariz-Karapinar coal region are of middle Miocene age and were deposited in a lacustrine environment. Coal in this formation is lignitic in rank (%Ro, random of eu-ulminite B is 0.37). These lignites have high inertinite content (up to 37.4%), which is higher than in any other Turkish lignites studied previously. Inertinite content in the region increases from the northeast to the southwest, possibly indicating oxidation of organic matter in the coal-forming environment due to lowering of the water level. Total sulfur content in the lignites ranges from 1.8 to 4.8%. High-rank coals present in the Upper Permian Yigiltepe Formation (%Ro, random is 0.66-0.70) contain more sulfur (Stot = 5.6-6.9%) and less inertinite (9.6-12.1%).

The reflectance of chitinozoa (%ChR0) was investigated as an alternative technique of determining the level of thermal maturity of organic-rich Palaeozoic rocks in southern Ontario. These sedimentary strata, which include the Ordovician Collingwood Member and the Blue Mountain Formation, as well as the Devonian Marcellus Formation, lack vitrinite precluding the application of a standard vitrinite reflectance (%VR0) technique. ChR0 shows a proportional increase at marginal to moderate maturities, being on average 20 to 25% higher than expected vitrinite reflectance. The reflectance data fall into a very narrow range showing a high degree of consistency for each lithostratigraphic unit. The average ChR0 are as follows: Collingwood Mbr 0.63% (Georgian Bay area) and 0.88% (Toronto area), Blue Mountain Fm 0.92%, Marcellus Fm 0.68%. Correlation with more conventional optical and geochemical maturity parameters obtained from the same set of samples (fluorescence of Tasmanites, Leiosphaeridia and Gloeocapsomorpha alginite, Rock-Eval Tmax, extract data, distribution of terpanes and steranes in extracts) indicates that, within the area of study, the beginning of the catagenetic stage corresponds to ChR0=0.65% (equivalent VR=0.50%) whereas the threshold of significant oil generation is reached at ChR0=0.9% (equivalent VR=0.70%). Therefore the Blue Mountain Formation is thermally mature with respect to hydrocarbon generation throughout the whole area of study. The Collingwood shales are mature only in the Toronto area while those occurring in the Georgian Bay area as well as the Marcellus shales have yet to enter the main stage of hydrocarbon generation. This integrated approach of assessing thermal maturity shows that ChR0, when constrained with other maturity parameters, is a very reliable indicator of thermal maturity in Lower to Middle Palaeozoic sedimentary rocks.

A continental minerotrophic peatland in Alberta was studied for its botanical, petrographical, mineralogical and geochemical characteristics. Changes in peat stratigraphy and mineralogy are related, and development toward oligotrophic conditions is recorded. Elemental concentration and distribution vary in the peat profile, reflecting the influence of natural and anthropogenic factors on peat geochemistry. Many elements (Al, As, Ba, Co, Cr, Fe, Mn, Th, V) accumulate in the zone of water table fluctuation as a result of changes in redox chemistry. The relative elemental concentration at the surface and near-surface (e.g., As, Cr, Sb, Th, Ti, V) may also be attributed to atmospheric deposition related to anthropogenic activity. Chemical analysis (Al, Fe, Mg, Na, Si, Ti) also reveals the presence of a non-visible volcanic-ash-rich layer near the base of the peat profile, possibly Mazama tephra. This study provides evidence of pyrite formation in a freshwater peat-forming environment, associated with high-sul...

Results of ash chemistry composition on highwall channel samples, coal seams 1–6, cut W86, Whilewood Mine, reveal that low SiO2 / Al2O2 ratios are associated with high electrostatic precipitator (ESP) opacity. This ratio varies from 2·26 in seam 3 to 5·81 in seam 4, and is a good indicator of the clay minerals present in the coal. A low ratio (

Coal from the deposit of Plakia, Island of Crete, Greece, was examined petrologically for the determination of rank, maceral composition, and trace element geochemistry. The coal is of lignite to subbituminous B rank (%R o,ran = 0.36-0.44). Some samples are rich in resinite. This was subdivided into two groups based on its morphological and fluorescence properties. Mineral matter in the coals consists predominantly of silicate and sulphur-bearing minerals. The low temperature ash (LTA) is dominated by quartz, illite and gypsum, whereas the mineralogy of the high temperature ash (HTA) is comprised of silicates, Fe-bearing minerals and anhydrite. The coals are enriched in the elements As, Cr, Co, Cu, Mn, Mo, Rb, Se, U, V, Ce and Nd, when compared to world coals. Thorium, Zn and most of the REEs are present in concentrations within the mean range for most coals. Bromine, Cl and Se are volatilized at 1000°C, while U, Th, V, Cr, Co, Cu, Mo and Zn are enriched in the coal ash by a factor of 2–8. Also, there are positive correlations among As, Mo, U and S in the coal, as well as between the amount of sulphur-bearing minerals in coal ash and total concentration of As, Mo and U in the coal. Sulphur content in the coals ranges from 3.5% to 5.7%; approximately 4.8–33.6% of sulphur is volatilized at 120°C and a large percentage of total sulphur is volatilized at 1000°C. This has an important implication for the use of the Plakia coals for power generation, because of the emission of SO x compounds to the atmosphere. Fluidized bed combustion and flue gas desulphurization processes are recommended to achieve reduction in trace element and sulphur emissions. The HTA is relatively acidic and the high content of SiO 2 in the ash may create erosion problems in the boilers. Finally, potential problems of slagging and fouling are anticipated, based on the indices (e.g., base-acid ratio) of the lignitic ash.

Subbituminous coals, taken from a freshly mined open pit as well as from nine drillholes in the Whitewood Mine, Alberta, were analyzed for their elemental and radionuclide concentration. Furthermore, the coal ash was analyzed for major oxides, and a comparison was made with coals of similar rank and present only 12 km away, in the Highvale Mine. The Whitewood Mine coals are “clean“ by world standards and do not contain any environmentally deleterious elements in excess amounts. They are suitable for utilization, but care should be taken to minimize the negative opacity effects on the electrostatic precipitators (ESPs). The low Na2O content in the coals, particularly in the open-pit samples, may affect ash resistivity. This could result in a decrease in the flow of current and thus a decrease in the precipitator efficiency. Certain trends of major oxides in the coal ash are observed in a north-south direction and are discussed, with particular emphasis on the Na2O distribution in the six coal seams. The Wh...

Mineralogical analysis of the Highvale Mine coals using X-ray diffraction (XRD) shows quartz, kaolinite, illite, and feldspars to dominate. Minor amounts of carbonate and unknown hydrate minerals are also present, and most minerals reported by XRD have been verified by scanning electron microscopy-energy-dispersive X-ray spectrometry (SEM-EDX) on selected samples using back-scattered electron imaging on coal pellets, The coal ash indices show the Highvale Mine coals to have low to medium propensity to form slagging or fouling deposits in the boilers. The relationship between ash content of mill samples and opacity in the electrostatic precipitators (ESPs) is not clear. However, there appears to be a correspondence between ash resistivity and ESP performance. As resistivity is a function of ash chemical composition, the differences in ash composition, notably in its Fe2O3 content, may have contributed to the increase in opacity recorded for seam 1. The production of submicron particles, via fragme...

This study reports on the enrichment and depletion of elements in selected suites of subbituminous coals from the Highvale Mine, Alberta, Canada and in their 120°C, 400°C and 800°C ashes. All elements analyzed in the raw coal are within the world range for coals and some small variations in elemental concentration were noted due to variations in ash content of the samples. Ashing at 120°C resulted in an enrichment of all elements by a factor of 1.5 × to 6.5 × in one suite of samples and by a factor of 5 × to 11× in the other suite. Generally, the elements Br and Se are enriched by a lower factor than other elements, Mo is absent in all 120°C ashed samples and the samples with the higher ash content show a smaller elemental enrichment than samples with lower ash content (cleaner coals). All elements in the 400°C ashed samples are enriched by a factor of 1.5 × to 6.5 × in one suite of samples and by 1.5 × to 9.5 × in the other. Surprisingly, the elements Br, CI and Se are enriched two- to sixfold, pointing ...

The concentration of boron in Australian and Canadian coals determined using atomic emission spectrometry (AES), inductively coupled plasma spectrometry (ICP-AES) and prompt gamma-ray spectrometry is summarized in order to assess the variation of B content in coal with respect to rank, age, geological setting (in-seam and stratigraphic) and the degree of paleosalinity of the coal-forming environment. This study indicates that no/or very complex relations exist between boron and rank (subbituminous to anthracite). Variations of B with ash content for Canadian coals of different age (Devonian to Oligocene-Eocene) indicate that the B content of coals is not governed by the age of the coal. There is some evidence of variation of B with maceral content in Canadian coals, particularly as related to the inertinite and vitrinite content of coals. The B content of coal seams is sensitive to the environment of deposition, with B contents remaining relatively stable and within the range of values designated for each depositional setting. However, B values may show variation in the same seam laterally due to changes of the environment of deposition and/or the enrichment of B by a secondary source. The vertical variation of B in a coal-bearing section or strata is related to depositional environment and lithology of rock. There is often little variation in B content for coal layers as compared to the partings (dirt bands). The B content of partings in a coal-bearing strata may vary greatly as compared to the coal seams. After reappraising earlier work, and on the basis of more recent studies on Australian and Canadian coals, it is proposed that the following ranges of values for B in coal indicate the degree of marine influence during the early stages of coalification: • up to 50 ppm B: freshwater-influenced coals • 50–110 ppm B: mildly brackish water-influenced coals • >110 ppm B: brackish water-influenced coals. Using these criteria, assessments are given for the degree of marine influence on Canadian and Australian coals.

A suite of liptinite-rich coals from the Lower Cretaceous Mannville Group in the subsurface of Alberta, Canada has been studied with respect to its organic petrology and organic geochemistry. The samples are rich in fluorescing vitrinite (perhydrous), sporinite, cutinite, exsudatinite and bituminite. Rock-Eval analysis shows that the coals are enriched in hydrogen (hydrogen index up to 320 mg HC/g TOC) and depleted in oxygen (oxygen index up to 11 mg CO2/g TOC). The value of Tmax ranges from 445 to 460°C, indicating a late catagenic level of thermal maturity (equivalent to %Ro = 1.0–1.1), but the vitrinite reflectance is between 0.68 and 0.81%, indicating that it is lowered by as much as 0.4%. The pyrolysis chromatograms of the coal samples are dominated by substituted benzenes (toluene and xylenes), naphthalenes, phenanthrenes, substituted phenols (cresols) and small amounts of n-alkanes in the range C20+. Gas chromatography-mass spectrometry of the steranes and terpanes indicates little or no contribution of allochthonous bitumen to the coals. In addition, the mz = 217 sterane traces are dominated by C29 compounds with little C27 and C28; this, along with the high terpane to sterane ratio (mz 191 to mz 217 = 8.8) indicates that the bitumen was generated from terrestrially derived organic matter. The bitumen in the coals has most likely been autogenerated by the coals themselves in response to thermal stress. The originally sapropelic coals were probably deposited in an anaerobic environment and were much enriched in hydrogen. This study shows that terrigenous organic matter, when associated with an anomalous liptinite content, may have the potential to generate bitumen.

Concentrations of Sb, As, B, Br, Cd, Cl, Cr, Co, Cu, F, Pb, Hg, Mo, Se, Th, U and Zn have been determined in channel samples collected at all active mines in the Peace River (northeastern B.C.) and East Kootenay (southeastern B.C.) coalfields. Means in whole-seam samples from both regions (30 samples), excepting those elements which are below detection limits in some samples, are as follows: Sb 1.0 ppm; As 1.6 ppm; Br 1.0 ppm; Cl 136 ppm; Cr 21 ppm; Co 2.3 ppm; Cu 18 ppm; F 518 ppm; Hg 50 ppb; Th 3.2 ppm; and U 1.8 ppm. By world standards, mean concentrations of Cl, Br, Co, As, Hg and Pb in B.C. coals are relatively low, while concentrations of F are relatively high. Mean values of Cl and Th are statistically higher in Peace River Coals than in East Kootenay coals; concentrations of other elements are similar in the two regions. Consistent stratigraphic variations in the concentrations of elements generally do not occur, although several of the elements, namely Sb, As, Cr, Co, Cu, F, Th aand U, achieve their highest concentrations in the middle one-third of the Mist Mountain Formation (East Kootenay) and in the upper one-half of the Gates Formation coal-bearing section (Peace River). These trends may be more related to variations in ash content of the samples than to stratigraphic controls. Based on correlations, almost all of the eleven elements whose concentrations consistently exceed detection limit appear to have strong inorganic associations. Exceptions are Cl and Br, which appear to be associated predominantly with the organic fraction.

The variation of maturity indicators with respect to mineral matrix and organic matter types was examined from the Mesozoic succession of Melville Island, Arctic Canada. The T max values of non-marine deltaic samples show a much greater degree of scattering with respect to vitrinite reflectance, whereas the marine samples show a narrow distribution. This behaviour is most likely to be a consequence of the differences in the chemical properties of terrestrial versus marine organic matter, which is a function of the organic matter type and of the depositional environment. The non-marine deltaic samples also show higher T max values than their marine counterparts, an indication either of the higher degree of oxidation of the non-marine deltaic samples or of the fact that type III organic matter has intrinsically higher T max values than types I and II organic matter at the same maturity level. Based on the relationship between hydrogen index (HI) and vitrinite reflectance (%Ro), it appears that marine organic matter is more sensitive (high negative correlation) to thermal maturity changes than non-marine deltaic organic matter. No clear correlation between S 2 (hydrocarbon yield) and %Ro (maturity) could be seen in the suite of samples. Both fluorescence parameters ( λ max and R G quotient) increase with maturity but the trends have different slopes for the various macerals, a function of their marine or non-marine origin.

The elemental distribution in peat deposits from Fraser delta, British Columbia, Canada were examined on peat ashed at low temperature (90°C) using INAA, DCP, andAA. Chlorine, B, Br, Mo, Na, S, and U are sensitive indicators of the depositional environment of these peats. The distribution of elements is related to water salinity. High concentrations of Cl and Na are encountered in samples deposited in brackish water environment and in the contact between the peat and the sea water. The concentration of Cl and Na decrease with decreasing distance from the contact with sea water. Silicon has the lowest concentration on the top of the fresh water peat and the highest on or near the top of brackish water peat. The concentration of the “authigenic uranium” in peats appears to be related to water salinity. The highest values are found in brackish water peat, indicating that uranium is possibly concentrated by its interaction with salt and carbonates. Compared to the Clark value, the only elements enric...

Pyrite concentrates were obtained from seven successive coal seams of Upper Carboniferous age in the Sydney Coalfield of Nova Scotia. These concentrates were analyzed for forty-nine trace metals and oxides using INAA and ICPES. The data indicate that trace amounts of other sulphide phases (inclusions as arsenopyrile, galena, chalcopyrite), presumed epigenetic clay minerals, and zircon inclusions are associated with pyrite concentrates. The content of rare earths and actinides in these pyrites are age dependent and tend to be more highly concentrated in the younger seams. Pyritic oxidation in coal and resultant formation and dissolution of secondary sulphate minerals are one mechanism for trace-metal dispersion into the surface-water environment. The pyrite concentrates on average are arsenic-rich (range 240-2900 ppm, mean 1556 ppm). However, this As may form insoluble, stable organic-complexes, which remain as As-rich sediments in situ.

The variation of vitrinite reflectance with respect to mineral matrix (lithology), the thickness of coal seams and coal lenses and the type of organic matter was studied from two cores in a 550 m sedimentary succession from the Upper Jurassic to Lower Cretaceous Kootenay Group. The data obtained indicate that reflectance in high to low volatile bituminous coals (%RO, max = 0.8–1.35) with depth of burial is affected by the percentage of organic matter in the samples. A positive correlation between the vitrinite reflectance and the percentage of organic matter and a negative correlation with the percentage of mineral matter exist and the thicker the coal interval, the higher the vitrinite reflectance. Thick coal seams (>1 m) with a mineral content 20%. Vitrinite dispersed in sandstone and to a lesser extent siltstone and carbonaceous shale has the lowest reflectance. Variations in vitrinite reflectance may be attributed to chemical differences in the organic matter, possibly induced by degradation and diagenesis syn- or post-depositionally, and to the effect of some clay minerals present in the sediments, which may act as catalysts. Differences in the thermal conductivity of the strata have demonstratably not accounted for the observed variations in reflectance with lithology. The differences in the vitrinite reflectance of organic matter between lithotypes is substantial and is thus an important consideration in resolving the time-temperature history and generation of hydrocarbons from a sedimentary succession.

Organic matter present in uraniferous paleoplacer deposits in the Elliot Lake-Blind River region, Canada, falls into two distinct types based on morphology, reflectance in oil, and bireflectance. Organic matter of the second type is primary and biogenic and probably represents the metamorphosed remnants of cyanobacterial mats. It consists of finely laminated kerogens with high reflectance (%Romax — 4.02-7.31) and high bireflectance. Under cross-polars it shows a textural pattern similar to that of thinly laminated organic matter. The level of thermal maturation is in the range of prehnite-pumpellyite to lower greenschist metamorphic facies. The first type consists of homogeneous, globular, migrated bitumen. These bitumens are isotropic to weakly anisotropic with a reflectance ranging from 0.72 to 1.32% (Romax)Globular bitumen is essentially unmetamorphosed and follows the (normal) bitumen maturation pathway. Both types of organic matter have contributed to the uraniferous mineralization of the El...

Elliot Lake organic matter falls into two main groups: (1) stratiform kerogens with reflectance from 2.63 to 7.31% Ro(max), exhibit a high level of aromaticity and low atomic H/C ratios (0.41 − 0.60): (2) less aromatic disseminated globules, most resembling solid bitumen are of lower maturity, with Ro(max) from 0.72 to 1.32. and atomic H/C ratios 0.71 − 0.81. Stratiform kerogens, originated from cyanobacteria, have δ13C values from −15 to −25%. One exception with δ13C = − 31.8%, may have originated from methanogenic source biota: thus two genetically distinct populations of kerogen are tentatively recognized in Elliot Lake metasediments. Globular bitumens, remobilized by hydrous pyrolysis from kerogen, exhibit δ13C values ranging from −25% tp −33%0. The overall isotopic bimodality among Elliot Lake organic material is explained by analogy to petroleum generation from particulate kerogen that matured under conditions of catagenesis to metagenesis and was subjected to radiation over a long time. Barium, U, Th, Au, Pt, Pd and REE contents of Elliot Lake stratiform kerogen greatly exceed of average black shales. Except for As, Pt, Pd and Au, all metals (Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Se, Rb, Sr, Ag, Sb, Cs, Ba, Hf, Ta, W, Hg, Th and U) are more concentrated in stratiform kerogens than in the derivative bitumen. This signals a significant role for a low-temperature transfer of noble metals to migrating bitumen.

Coals from western Canada were examined for structural changes occurring during oxidation, carbonization and hydrogenation by means of FT-IR spectroscopy, optical microscopy and chemical analysis. The coals are of Cretaceous to Eocene age, ranging in rank from subbituminous C to medium-volatile bituminous (0.42–1.47% R o ). Results indicate that the reactivity of the coals during the above mentioned processes depends on rank and petrological composition. Infrared spectroscopy is shown to be sensitive to the molecular structural changes occurring during these processes and provides a chemical basis for interpreting data from chemical analysis and optical microscopy.

Thermally metamorphosed bitumen samples associated with an Archean ultramafic volcanic sequence near Timmins, Ontario, Canada were examined using reflected and transmitted light microscopy and X-ray diffraction. The bitumen occurs in aphanitic to fine-grained chemical and clastic meta-sediments intercalated with the volcanic flows and in derived metasedimentary xenoliths engulfed in the flows. This thermally altered bitumen was apparently derived from biogenic organic carbon in the original Archean sediments. The organic components of the samples consist of epi-impsonite to cata-impsonite and pyrolytic carbons. The latter occur in conical, layered, radial and spherulitic forms. The maximum temperature of formation of the pyrolytic carbon has been estimated at 700°C, which is consistent with its occurrence in xenoliths in these high temperature (1300–1500°C) volcanic flows.